血小板活化因子对大鼠气道平滑肌细胞的促增殖作用

目的：研究血小板活化因子(platelet-activating factor, PAF)对离体培养的大鼠气道平滑肌细胞(airway smooth muscle cell, ASMC)增殖的影响。方法： 离体培养大鼠气道平滑肌细胞，细胞分为对照组、PAF组；后者又 分为10-6、10-7、10-8、10-9 mol·L-1 4小组，MTT(四唑盐)比色法检测细胞增殖活力并确定PAF最佳作用浓度；用最佳作用浓度刺激ASMC 12 h、24 h、36 h以流式细胞仪测定细胞周期，免疫细胞化学染色(SABC 法)检测该PAF刺激48 h后细胞核增殖抗原(PCNA)的表达。 结果： PAF在10-6-10-9 mol·L-1范围内均能促进ASMC的增殖(P<0.01)，且10-7 mol·L-1时增殖作用最强；用这一最佳浓度的PAF干预12 h后，G0/1期细胞百分比(68.67%)明显低于对照组(85.57%)(P<0.01)；PCNA免疫细胞化学染色发现10-7mol·L-1的PAF作用48 h后，ASMC的PCNA表达率为(71.05±1.22)%，显著高于对照组(53.27±2.56)% (P<0.05)。结论： PAF能以时间依赖方式促进ASMC的增殖，但该作用并不表现为浓度依赖性。

PAF promotes proliferation of smooth muscle cells of rat airway

AIM: To study the effect of platelet-activating factor(PAF) on proliferation of cultured rat airway smooth muscle cells(ASMCs).METHODS: The cells were divided into control group and PAF group. The cells in PAF group were subdivided into four small groups by concentrations of PAF 10-6, 10-7, 10-8, 10-9 mol·L-1, MTT assay was used not only to investigate the effects of PAF on proliferation of ASMC but also to confirm the optimal concentration. Flow cytometry and immuneohistochemistry for proliferating cell nuclear antigen (PCNA) were also used to analyse its function on proliferation of ASMC.RESULTS: PAF (10-6-10-9mol·L-1) stimulated the cell proliferation and 10-7mol·L-1 PAF reached the maximal effect. The cell percentage of the ASMCs of 107 mol·L-1 PAF subgroup at G0/1 phase (68.67%) was much lower than that of control group (85.57%, P<0.01), in this subgroup, the percentage of expression of PCNA at 48 h (71.05%±1.22%) was significantly increased compared with the control group (53.27%±2.56%, P<0.05).CONCLUSION: PAF can stimulate the proliferation of cultured ASMC in a time-dependent, but not dose-dependent manner.